Spermatogenesis is a fundamental process that requires a tightly controlled epigenetic event in spermatogonial stem cells(SSCs).The mechanisms underlying the transition from SSCs to sperm are largely unknown.Most stud...Spermatogenesis is a fundamental process that requires a tightly controlled epigenetic event in spermatogonial stem cells(SSCs).The mechanisms underlying the transition from SSCs to sperm are largely unknown.Most studies utilize gene knockout mice to explain the mechanisms.However,the production of genetically engineered mice is costly and time-consuming.In this study,we presented a convenient research strategy using an RNA interference(RNAi)and testicular transplantation approach.Histone H3 lysine 9(H3K9)methylation was dynamically regulated during spermatogenesis.As Jumonji domain-containing protein 1A(JMJD1A)and Jumonji domain-containing protein 2C(JMJD2C)demethylases catalyze histone H3 lysine 9 dimethylation(H3K9me2),we firstly analyzed the expression profile of the two demethylases and then investigated their function.Using the convenient research strategy,we showed that normal spermatogenesis is disrupted due to the downregulated expression of both demethylases.These results suggest that this strategy might be a simple and alternative approach for analyzing spermatogenesis relative to the gene knockout mice strategy.展开更多
Testicular development is an important biological process in male and requires interaction between the male germ cells and somatic cells.However,the mechanisms of testicular development in livestock,particularly in ca...Testicular development is an important biological process in male and requires interaction between the male germ cells and somatic cells.However,the mechanisms of testicular development in livestock,particularly in cattle,are poorly understood.Furthermore,cellular heterogeneity hinders the profiling of different cell types at different developmental stages.In this study,we first performed a single-cell transcriptomic study of the bovine testis development during puberty by using 10×genomics single-cell RNA sequencing(scRNA-seq).By collecting the scRNA-seq data from 11,083 cells from prepubertal and pubertal bovine testes,a high-resolution scRNA-seq atlas was described,identifying 9 somatic and 13 spermatogenic clusters.We also distinguished several stage-specific marker genes for bovine germ cells and somatic cells,such as GRAF2 and MORC1 for SSC(spermatogonial stem cells),HJURP and TCF19 for differentiating spermatogonia,ARSE for immature Sertoli,CLEC12B for mature Sertoli,LOC112441470 for Leydig.In conclusion,we have examined the transcription levels and constructed the single-cell developmental maps of germ cells and somatic cells during testicular development in Angus cattle.The datasets provided new insights into spermatogenesis and testicular somatic cell development in cattle.展开更多
Male germ cells employ specific metabolic pathways throughout their developmental stages.In a previous study,we discovered heightened expression of pyruvate kinase M(PKM),a pivotal glycolytic enzyme,in spermatogonia a...Male germ cells employ specific metabolic pathways throughout their developmental stages.In a previous study,we discovered heightened expression of pyruvate kinase M(PKM),a pivotal glycolytic enzyme,in spermatogonia and spermatids.To gain deeper insights into PKM's roles in spermatogenesis,sperm function,and male fertility,we engineered a conditional-knockout mouse model(Pkm-vkO mice)to selectively disrupt the Pkm gene within germ cells.Despite maintaining regular testicular histology and sperm morphology,the male Pkm-vko mice were infertility,characterized by significant impairments in sperm motility and adenosine triphosphate(ATP)generation.In addition,Pkm-null spermatozoa exhibited similar deficits in protein tyrosine phosphorylation linked to capacitation,as well as compromised performance in in vitro fertilization experiments.To conclude,PKM's presence is not obligatory for the entirety of spermatogenesis in male germ cells;however,it emerges as a critical factor influencing sperm motility and overall male fertility.展开更多
In the coastal environment,the co-occurrence of antibiotic and nanoplastic pollution is common.Investigating their individual and combined toxicity to marine organisms is of great necessity.In the present study,the re...In the coastal environment,the co-occurrence of antibiotic and nanoplastic pollution is common.Investigating their individual and combined toxicity to marine organisms is of great necessity.In the present study,the reproductive toxicity of sulfamethazine(SMZ)and nanoplastics(polystyrene,PS)via the dietary route on the spermatogenesis of marine medaka(Oryzias melastigma)was examined.After 30 d of dietary exposure,SMZ alone decreased the gonadosomatic index(GSI)value(~35%)and the proportion of undifferentiated type A spermatogonia(A_(und))(~40%),probably by disrupting the testicular sex hormone production,the spermatogenesis-related growth factor network and the balance of apoptosis.Individual exposure to PS did not affect the GSI value or the proportions of germ cells at different developmental stages,but dysregulated the expression of several spermatogenesis-related genes.Interestingly,the presence of PS alleviated the decreased GSI value caused by SMZ.This alleviation effect was achieved by enhancing the spermatogonia differentiation instead of reversing the suppressed self-renewal of A_(und),suggesting that the mixture of PS and SMZ could cause reproductive effects in a different way.These findings expand our knowledge of threats of ubiquitous antibiotic and nanoplastic pollution to fish reproduction and population.展开更多
Spermatogenic cell heterogeneity is determined by the complex process of spermatogenesis differentiation.However,effectively revealing the regulatory mechanisms underlying mammalian spermatogenic cell development and ...Spermatogenic cell heterogeneity is determined by the complex process of spermatogenesis differentiation.However,effectively revealing the regulatory mechanisms underlying mammalian spermatogenic cell development and differentiation via traditional methods is difficult.Advances in technology have led to the emergence of many single-cell transcriptome sequencing protocols,which have partially addressed these challenges.In this review,we detail the principles of 10x Genomics technology and summarize the methods for downstream analysis of single-cell transcriptome sequencing data.Furthermore,we explore the role of single-cell transcriptome sequencing in revealing the heterogeneity of testicular ecological niche cells,delineating the establishment and disruption of testicular immune homeostasis during human spermatogenesis,investigating abnormal spermatogenesis in humans,and,ultimately,elucidating the molecular evolution of mammalian spermatogenesis.展开更多
Objective:To investigate the successive morphological stages of spermatogenesis,hormonal regulation,and testosterone profile in dromedary camel reproduction.Methods:Testicular tissue samples were obtained from 12 drom...Objective:To investigate the successive morphological stages of spermatogenesis,hormonal regulation,and testosterone profile in dromedary camel reproduction.Methods:Testicular tissue samples were obtained from 12 dromedary bull camels aged 7 to 8 at a local abattoir.The histological assessment involved tissue processing,hematoxylin and eosin(H&E)staining,and examination under a microscope.Stereological analysis,germ cell identification,and assessment of seminiferous tubules and maturation were conducted.Testosterone assay was performed by radioimmunoassay using blood samples collected at regular intervals.Results:The study revealed 12 phases of the dromedary camel's seminiferous epithelium cycle,highlighting distinct morphological characteristics and cellular processes.Acrosomal migration,maturation,cap formation,and the Golgi-mediated synthesis of proacrosomal vesicles were also explained in dimension,as were the steps of acrosome biogenesis.Spermatids and mature sperm cells were present when spermatogenesis phases were examined.An analysis of the dimensions of seminiferous tubules revealed specific measures for diameter,area,and epithelial height about luminal characteristics.Moreover,there were noticeable variations in the serum testosterone concentrations during the study period,indicating temporal dynamics.Conclusions:This study outlines the spermatogenesis process in dromedary camels across 12 stages,emphasizing cellular dynamics and acrosomal biogenesis.It also provides seminiferous tubule measurements and observes seasonal testosterone fluctuations,offering insights into reproductive regulation and potential strategies for camel breeding conservation.展开更多
BACKGROUND Pituitary stalk interruption syndrome(PSIS)is a rare anatomical defect of the pituitary gland falling under the spectrum of holoprosencephaly phenotypes.It is characterized by a deficiency in anterior pitui...BACKGROUND Pituitary stalk interruption syndrome(PSIS)is a rare anatomical defect of the pituitary gland falling under the spectrum of holoprosencephaly phenotypes.It is characterized by a deficiency in anterior pituitary hormones,such as growth hormone,gonadotropins,and thyroid hormones.Due to the syndrome's rarity and nonspecific manifestations,there is a lack of standardized treatment strategies.Consequently,early diagnosis through imaging and on-time intervention are crucial for improving patients’outcomes.CASE SUMMARY A 30-year-old man presented with absent secondary sexual characteristics and azoospermia.Laboratory evaluation revealed a deficiency in gonadotropins,while thyroid function was mostly within normal ranges.Magnetic resonance imaging of the pituitary gland showed pituitary stalk agenesis,hypoplasia of the anterior pituitary,and ectopic posterior pituitary,leading to the diagnosis of PSIS.Initially,the patient underwent 6 mo of gonadotropin therapy without significant changes in hormone levels and secondary sexual characteristics.Pulsatile gonadotropin-releasing hormone therapy was then administered,resulting in the detection of sperm in the semen analysis within 3 mo.After 6 mo,routine semen tests showed normal semen quality.The couple faced challenges in conceiving due to abstinence and underwent three cycles of artificial insemination,which was unsuccessful.They also attempted in vitro fertilization,but unfortunately,the woman experienced a miscarriage 10 wk after the embryo transfer.CONCLUSION Early detection,accurate diagnosis,and timely treatment are crucial in improving the quality of life and fertility of PSIS patients.展开更多
Morphology of the male reproductive system, chromosome behaviors during meiosis and spem tail structures in Homoptera and Heteroptera are compared in this paper. The sheathed testis is found in Fulgoroidea and Heterop...Morphology of the male reproductive system, chromosome behaviors during meiosis and spem tail structures in Homoptera and Heteroptera are compared in this paper. The sheathed testis is found in Fulgoroidea and Heteroptera, and unsheathed testis occurs in Cicadoidea, Cicadelloidea, Cercopoidea, Membracoidea, Psyloidea, Aphidoidea, Aleyrodoidea and Coccoidea. The testis also can be divide into three types by the shape of testicular follicles. The sphere-shaped type is found in Cicadoidea, Cicadelloidea, Cercopoidea, Membracoidea, Aphidoidea and Aleyrodoidea, the tube-shaped type observed in Fulgoroidea, Psyloidea and Coccoidea, and the lamella-shaped type represented by Heteroptera. It is suggested the unsheathed testis may be the primitive type in Homoptera. Meiosis can be divided into 6 type at least, i.e. 1） Cicadoid type; 2） Fulgoroid type; 3） Psyloid type; 4） Aphidoid type; 5） Aleyrodoid type; and 6） Coccoid type. At least four groups exhibit a diffuse stage during meiosis prophase l, they are Psyloidea, Fulgoroidea, Coccoidea and Heteroptera. Sperm tail structures are similar to those reported from other insects with a typical 9＋9＋2 axoneme except that in Aleyrodoidea and Coccoidea whose sperm tail is degenerated.展开更多
Phosphoribosyl-pyrophosphate synthetase 2(PRPS2)is a rate-limiting enzyme and plays an important role in purine and pyrimidine nucleotide synthesis.Recent studies report that PRPS2 is involved in male infertility.Howe...Phosphoribosyl-pyrophosphate synthetase 2(PRPS2)is a rate-limiting enzyme and plays an important role in purine and pyrimidine nucleotide synthesis.Recent studies report that PRPS2 is involved in male infertility.However,the role of PRPS2 in hypospermatogenesis is unknown.In this study,the relationship of PRPS2 with hypospermatogenesis and spermatogenic cell apoptosis was investigated.The results showed that PRPS2 depletion increased the number of apoptotic spermatogenic cells in vitro.PRPS2 was downregulated in a mouse model of hypospermatogenesis.When PRPS2 expression was knocked down in mouse testes,hypospermatogenesis and accelerated apoptosis of spermatogenic cells were noted.E2F transcription factor 1(E2F1)was confirmed as the target gene of PRPS2 and played a key role in cell apoptosis by regulating the P53/Bcl-xl/Bcl-2/Caspase 6/Caspase 9 apoptosis pathway.Therefore,these data indicate that PRPS2 depletion contributes to the apoptosis of spermatogenic cells and is associated with hypospermatogenesis,which may be helpful for the diagnosis of male infertility.展开更多
To investigate the effect of arsenic on spermatogenesis. Methods: Mature (4 months old) Wistar rats were intraperitoneally administered sodium arsenite at doses of 4, 5 or 6 mg-kg^-day1 for 26 days. Different varietie...To investigate the effect of arsenic on spermatogenesis. Methods: Mature (4 months old) Wistar rats were intraperitoneally administered sodium arsenite at doses of 4, 5 or 6 mg-kg^-day1 for 26 days. Different varieties of germ cells at stage VII seminiferous epithelium cycle, namely, type A spermatogonia (ASg), preleptotene spermatocytes (pLSc), midpachytene spermatocytes (mPSc) and step 7 spermatids (7Sd) were quantitatively evaluated, along with radioimmunoassay of plasma follicle-stimulating hormone (FSH), lutuneizing hormone (LH), testosterone and assessment of the epididymal sperm count. Results: In the 5 and 6 mg/kg groups, there were significant dose-dependent decreases in the accessory sex organ weights, epididymal sperm count and plasma concentrations of LH, FSH and testosterone with massive degeneration of all the germ cells at stage VII. The changes were insignificant in the 4 mg/kg group. Conclusion: Arsenite has a suppressive influence on spermatogenesis and gonadotrophin and testosterone release in rats.展开更多
Spermatogenesis is a complex process regulated by endocrine and testicular paracrine/autocrine factors. Gonadotropins are involved in the regulation of several testicular paracrine factors, mainly of the IL-1 family a...Spermatogenesis is a complex process regulated by endocrine and testicular paracrine/autocrine factors. Gonadotropins are involved in the regulation of several testicular paracrine factors, mainly of the IL-1 family and testicular hormones. Testicular cytokines and growth factors (such as IL-1, IL-6, TNF, IFN-γ, LIF and SCF) were shown to affect both the germ cell proliferation and the Leydig and Sertoli cells functions and secretion. Cytokines and growth factors are produced by immune cells and in the interstitial and seminiferous tubular compartments by various testicular cells, including Sertoli, Leydig, peritubular cells, spermatogonia, differentiated spermatogonia and even spermatozoa. Corresponding cytokine and growth factor receptors were demonstrated on some of the testicular cells. These cytokines also control the secretion of the gonadotropins and testosterone in the testis. Under pathological conditions the levels of pro-inflammatory cytokines are increased and negatively affected spermatogenesis. Thus, the expression levels and the mechanisms involved in the regulation of testicular paracrine/autocrine factors should be considered in future therapeutic strategies for male infertility.展开更多
Aim:To determine the effect of oral administration of an aqueous extract from the roots of Lepidium meyenii(maca)on spermatogenesis in adult male rats.Methods;Male rats received an aqueous extract of the root(66.7 mg ...Aim:To determine the effect of oral administration of an aqueous extract from the roots of Lepidium meyenii(maca)on spermatogenesis in adult male rats.Methods;Male rats received an aqueous extract of the root(66.7 mg in onemL)twice a day for 14 consecutive days.Results:Treatment with Lepidium meyenii resulted in an increase in theweights of testis and epididymis but not the seminal vesicle weight.The length and frequency of stages IX-XIV seminif-erous tubules,where mitosis occurred,were increased and stages I-VI were reduced in rats treated with Lepidiummeyenii.Conclusion;The Lepidium meyenii root invigorates spermatogenesis in male rats by acting on its initialstages(IX-XIV).展开更多
Aim： To investigate the expression and subcellular localization of chemokine-like factor superfamily 2 （CKLFSF2） in human testis and its potential role in spermatogenesis. Methods： A specific polyclonal antibody a...Aim： To investigate the expression and subcellular localization of chemokine-like factor superfamily 2 （CKLFSF2） in human testis and its potential role in spermatogenesis. Methods： A specific polyclonal antibody against CKLFSF2 was raised. The expression and cellular localization of CKLFSF2 in the seminiferous tubules was checked by immunohistochemistry method. Also, in situ hybridization was applied to localize the mRNA distribution. The EGFP- CKLFSF2 fusion protein was expressed in COS-7 cells to localize its subcellular location in vitro. In addition, the abnormal expression of CKLFSF2 in testes of patients with male infertility was assayed by reverse transcription polymerase chain reaction （RT-PCR） and immunohistochemistry methods. Results： Having a close correlation with spermatogenesis defects, CKLFSF2 was specifically expressed in meiotic and post-meiotic germ cells, which were localized to the endoplasmic reticulum （ER） near the Golgi apparatus. Conclusion： CKLFSF2 could play important roles in the process of meiosis and spermiogenesis, and might be involved in the vesicular transport or membrane apposition events in the endoplasmic reticulum.展开更多
The effects of diabetes mellitus include long-term damages, dysfunctions, and failures of various organs. An important complication of diabetes is the disturbance in the male reproductive system. Glucose metabolism is...The effects of diabetes mellitus include long-term damages, dysfunctions, and failures of various organs. An important complication of diabetes is the disturbance in the male reproductive system. Glucose metabolism is an important event in spermatogenesis. Moreover, glucose metabolism is also important for maintaining basic cell activity, as well as specific functions, such as motility and fertilization ability in mature sperm. Diabetic disease and experimentally induced diabetes both demonstrated that either type 1 diabetes or type 2 diabetes could have detrimental effects on male fertility, especially on sperm quality, such as sperm motility, sperm DNA integrity, and ingredients of seminal plasma. Epigenetic modifications are essential during spermatogenesis. The epigenetic regulation represents chromatin modifications including DNA methylation, histone modifications, remodeling of nucleosomes and the higher-order chromatin reorganization and noncoding RNAs. If spermatogenesis is affected during the critical developmental window, embryonic gonadal development, and germline differentiation, environmentally-induced epigenetic modifications may become permanent in the germ line epigenome and have a potential impact on subsequent generations through epigenetic transgenerational inheritance. Diabetes may influence the epigenetic modification during sperm spermatogenesis and that these epigenetic dysregulation may be inherited through the male germ line and passed onto more than one generation, which in turn may increase the risk of diabetes in offspring.展开更多
The blood-testis barrier （BTB） is found between adjacent Sertoli cells in the testis where it creates a unique microenvironment for the development and maturation of meiotic and postmeiotic germ cells in seminiferou...The blood-testis barrier （BTB） is found between adjacent Sertoli cells in the testis where it creates a unique microenvironment for the development and maturation of meiotic and postmeiotic germ cells in seminiferous tubes. It is a compound proteinous structure, composed of several types of cell junctions including tight junctions （TJs）, adhesion junctions and gap junctions （GJs）. Some of the junctional proteins function as structural proteins of BTB and some have regulatory roles. The deletion or functional silencing of genes encoding these proteins may disrupt the BTB, which may cause immunological or other damages to meiotic and postmeiotic cells and ultimately lead to spermatogenic arrest and infertility. In this review, we will summarize the findings on the BTB structure and function from genetically-modified mouse models and discuss the future perspectives.展开更多
We investigated whether letrozole （2.5 mg day-1） improves sperm count in non-obstructive azoospermia （NOA） patients. Four men were included in this study, and they had folliculo-stimulating hormone and other hormo...We investigated whether letrozole （2.5 mg day-1） improves sperm count in non-obstructive azoospermia （NOA） patients. Four men were included in this study, and they had folliculo-stimulating hormone and other hormone levels within the normal range and no varicoceles or chromosomal aberrations. These four patients were administered letrozole for 3 months. Sperm count, testicular volume, gonadotropin, testosterone （T） and estradiol （E2） blood levels were assessed before, during and 1 week after the suspension of treatment. All patients showed spermatozoa in their ejaculate, increased gonadotropin and T levels and lower E2 levels （P〈0.05 in all cases）, when letrozole was administered. This suggests that letrozole treatment might improve sperm count in an NOA sub-population; however, more studies, including the proper controls, are needed to confirm its efficacy.展开更多
Aim： To determine whether vasectomy away from the epididymal tail （via the inguinal canal） in rabbits can reduce the early postoperative effects on spermatogenesis. Methods： Twenty-nine normal male Japanese white ...Aim： To determine whether vasectomy away from the epididymal tail （via the inguinal canal） in rabbits can reduce the early postoperative effects on spermatogenesis. Methods： Twenty-nine normal male Japanese white rabbits （aged 4- 6 months） were subjected to unilateral close-ended （conventional） or open-ended （the cut end of the juxta-epididymal vas deferens not ligated） vasectomy via the inguinal canal. Ten days and 3 months after operation, testes, epididymides and vasa deferentia were removed and methacrylate resin-embedded sections prepared. The histology of the testis, epididymis and vas deferens was examined under light microscope, and the volume and diameter of the seminiferous tubules were quantitatively studied using stereological methods. Results： Neither of the methods of vasectomy led to apparent damage to spermatogenesis on the vasectomized side in comparison with the contralateral shamoperated side, but the juxta-epididymal vas deferens on the vasectomized side was highly distended and contained numerous sperm 3 months after operation. Conclusion： Vasectomy away from the cauda epididymis has no significant early postoperative effects on spermatogenesis in rabbits.展开更多
Both pulsatile gonadotropin-releasing hormone （GnRH） infusion and combined gonadotropin therapy （human chorionic gonadotropin and human menopausal gonadotropin [HCG/HMG]） are effective to induce spermatogenesis in...Both pulsatile gonadotropin-releasing hormone （GnRH） infusion and combined gonadotropin therapy （human chorionic gonadotropin and human menopausal gonadotropin [HCG/HMG]） are effective to induce spermatogenesis in male patients with congenital hypogonadotropic hypogonadism （CH H）. However, evidence is lacking as to which treatment strategy is better. This retrospective cohort study included 202 patients with CHH： twenty had received pulsatile GnRH and 182 had received HCG/HMG. Patients had received therapy for at least 12 months. The total follow-up time was 15.6 ± 5.0 months （range： 12-27 months） for the GnRH group and 28.7 ± 13.0 months （range： 12-66 months） for the HCG/HMG group. The median time to first sperm appearance was 6 months （95% confidence interval [CI]： 1.6-10.4） in the GnRH group versus 18 months （95% Ch 16.4-20.0） in the HCG/HMG group （P〈 0.001）. The median time to achieve sperm concentrations 〉5 x 106 m1-1 was 14 months （95% Ch 5.8-22.2） in the GnRH group versus 27 months （95% Ch 18.9-35.1） in the HCG/HMG group （P 〈 0.001）, and the median time to concentrations 〉10 x 106 m1-1 was 18 months （95% Ch 10.0-26.0） in the GnRH group versus 39 months （95% CI unknown） in the HCG/HMG group. Compared to the GnRH group, the HCG/HMG group required longer treatment periods to achieve testicular sizes of 〉4 ml, 〉8 ml, 〉12 ml, and 〉16 ml. Sperm motility （a ＋ b ＋ c percentage） evaluated in semen samples with concentrations 〉1 × 106 ml-1 was 43.7% ± 20.4% （16 samples） in the GnRH group versus 43.2% ± 18.1% （153 samples） in the HCG/HMG group （P= 0.921）. Notably, during follow-up, the GnRH group had lower serum testosterone levels than the HCG/HMG group （8.3 ±4.6 vs 16.2 ± 8.2 nmol 1-1, P 〈 0.001）. Our study found that pulsatile GnRH therapy was associated with earlier spermatogenesis and larger testicular size compared to combined gonadotropin therapy. Additional prospective randomized studies would be required to confirm these findings.展开更多
To clarify the functions and mechanism of stimulated by retinoic acid gene 8 （Stra8） in spermatogenesis, we analyzed the testes from Stra8 knockout and wild-type mice during the first wave of spermatogenesis. Compar...To clarify the functions and mechanism of stimulated by retinoic acid gene 8 （Stra8） in spermatogenesis, we analyzed the testes from Stra8 knockout and wild-type mice during the first wave of spermatogenesis. Comparisons showed no significant differences in morphology and number of germ cells at 11 days postpartum, while 21 differentially expressed genes （DEGs） associated with spermatogenesis were identified. We speculate that Stra8 performs many functions in different phases of spermatogenesis, such as establishment of spermatogonial stem cells, spermatogonial proliferation and self-renewal, spermatogonial differentiation and meiosis, through direct or indirect regulation of these DEGs. We therefore established a preliminary regulatory network of Stra8 during spermatogenesis. These results will provide a theoretical basis for further research on the mechanism underlying the role of Stra8 in spermatogenesis.展开更多
Mammalian spermatogenesis contains three continuous and organized processes, by which spermatogonia undergo mitosis and differentiate to spermatocytes, follow on meiosis to form haploid spermatids and ultimately trans...Mammalian spermatogenesis contains three continuous and organized processes, by which spermatogonia undergo mitosis and differentiate to spermatocytes, follow on meiosis to form haploid spermatids and ultimately transform into spermatozoa. These processes require an accurately, spatially and temporally regulated gene expression patterns. The microRNAs are a novel class of post-transcriptional regulators. Cumulating evidences have demonstrated that microRNAs are expressed in a cell-specific or stage-specific manner during spermatogenesis. In this review, we focus on the roles of microRNAs in spermatogenesis. We highlight that N6-methyladenosine(m6A)is involved in the biogenesis of microRNAs and miRNA regulates the m6A modification on mRNA, and that specific mi RNAs have been exploited as potential biomarkers for the male factor infertility, which will provide insightful understanding of microRNA roles in spermatogenesis.展开更多
基金financially supported by the Shandong Provincial Natural Science Foundation(No.ZR2021QC182).
文摘Spermatogenesis is a fundamental process that requires a tightly controlled epigenetic event in spermatogonial stem cells(SSCs).The mechanisms underlying the transition from SSCs to sperm are largely unknown.Most studies utilize gene knockout mice to explain the mechanisms.However,the production of genetically engineered mice is costly and time-consuming.In this study,we presented a convenient research strategy using an RNA interference(RNAi)and testicular transplantation approach.Histone H3 lysine 9(H3K9)methylation was dynamically regulated during spermatogenesis.As Jumonji domain-containing protein 1A(JMJD1A)and Jumonji domain-containing protein 2C(JMJD2C)demethylases catalyze histone H3 lysine 9 dimethylation(H3K9me2),we firstly analyzed the expression profile of the two demethylases and then investigated their function.Using the convenient research strategy,we showed that normal spermatogenesis is disrupted due to the downregulated expression of both demethylases.These results suggest that this strategy might be a simple and alternative approach for analyzing spermatogenesis relative to the gene knockout mice strategy.
基金supported by the National Natural Science Foundation of China(81770514)the 2020 Scientist Plus Engineer Program of Shaanxi Province,China(K4050422468)+2 种基金the Key Research&Development Plan of Shaanxi Province,China(2020NY-002)the Natural Science Basis Research Plan of Shaanxi Province,China(2023-JC-QN-0242)the China Agriculture Research System of MOF and MARA(CARS-37)。
文摘Testicular development is an important biological process in male and requires interaction between the male germ cells and somatic cells.However,the mechanisms of testicular development in livestock,particularly in cattle,are poorly understood.Furthermore,cellular heterogeneity hinders the profiling of different cell types at different developmental stages.In this study,we first performed a single-cell transcriptomic study of the bovine testis development during puberty by using 10×genomics single-cell RNA sequencing(scRNA-seq).By collecting the scRNA-seq data from 11,083 cells from prepubertal and pubertal bovine testes,a high-resolution scRNA-seq atlas was described,identifying 9 somatic and 13 spermatogenic clusters.We also distinguished several stage-specific marker genes for bovine germ cells and somatic cells,such as GRAF2 and MORC1 for SSC(spermatogonial stem cells),HJURP and TCF19 for differentiating spermatogonia,ARSE for immature Sertoli,CLEC12B for mature Sertoli,LOC112441470 for Leydig.In conclusion,we have examined the transcription levels and constructed the single-cell developmental maps of germ cells and somatic cells during testicular development in Angus cattle.The datasets provided new insights into spermatogenesis and testicular somatic cell development in cattle.
基金supported by the National Natural Science Foundation of China(No.81571488 and No.81771637).
文摘Male germ cells employ specific metabolic pathways throughout their developmental stages.In a previous study,we discovered heightened expression of pyruvate kinase M(PKM),a pivotal glycolytic enzyme,in spermatogonia and spermatids.To gain deeper insights into PKM's roles in spermatogenesis,sperm function,and male fertility,we engineered a conditional-knockout mouse model(Pkm-vkO mice)to selectively disrupt the Pkm gene within germ cells.Despite maintaining regular testicular histology and sperm morphology,the male Pkm-vko mice were infertility,characterized by significant impairments in sperm motility and adenosine triphosphate(ATP)generation.In addition,Pkm-null spermatozoa exhibited similar deficits in protein tyrosine phosphorylation linked to capacitation,as well as compromised performance in in vitro fertilization experiments.To conclude,PKM's presence is not obligatory for the entirety of spermatogenesis in male germ cells;however,it emerges as a critical factor influencing sperm motility and overall male fertility.
基金The National Natural Science Foundation of China under contract No.42106119the Department of Science and Technology of Fujian Province under contract Nos 2022J02052,2020J05175 and 2020J05178+1 种基金the Fujian Provincial Department of Ocean and Fisheries under contract No.FJHJF-L-2022-12the Yancheng Fishery High Quality Development Project under contract No.YCSCYJ2021023.
文摘In the coastal environment,the co-occurrence of antibiotic and nanoplastic pollution is common.Investigating their individual and combined toxicity to marine organisms is of great necessity.In the present study,the reproductive toxicity of sulfamethazine(SMZ)and nanoplastics(polystyrene,PS)via the dietary route on the spermatogenesis of marine medaka(Oryzias melastigma)was examined.After 30 d of dietary exposure,SMZ alone decreased the gonadosomatic index(GSI)value(~35%)and the proportion of undifferentiated type A spermatogonia(A_(und))(~40%),probably by disrupting the testicular sex hormone production,the spermatogenesis-related growth factor network and the balance of apoptosis.Individual exposure to PS did not affect the GSI value or the proportions of germ cells at different developmental stages,but dysregulated the expression of several spermatogenesis-related genes.Interestingly,the presence of PS alleviated the decreased GSI value caused by SMZ.This alleviation effect was achieved by enhancing the spermatogonia differentiation instead of reversing the suppressed self-renewal of A_(und),suggesting that the mixture of PS and SMZ could cause reproductive effects in a different way.These findings expand our knowledge of threats of ubiquitous antibiotic and nanoplastic pollution to fish reproduction and population.
基金supported by National Key Research and Development Program of China(2022YFD1302201,2023YFF1000904)the National Natural Science Foundation of China(32072806,32372970)+2 种基金Key Technologies Demonstration of Animal Husbandry in Shaanxi Province(20221086,20230978)Inner Mongolia Autonomous Region Competition Leaders(2022JBGS0025)Xinjian Ugur Autonouous Region Scientific Research and Innovation Platform Construction Project“State Key Laboratory of Genetic Improvement and Germplasm”。
文摘Spermatogenic cell heterogeneity is determined by the complex process of spermatogenesis differentiation.However,effectively revealing the regulatory mechanisms underlying mammalian spermatogenic cell development and differentiation via traditional methods is difficult.Advances in technology have led to the emergence of many single-cell transcriptome sequencing protocols,which have partially addressed these challenges.In this review,we detail the principles of 10x Genomics technology and summarize the methods for downstream analysis of single-cell transcriptome sequencing data.Furthermore,we explore the role of single-cell transcriptome sequencing in revealing the heterogeneity of testicular ecological niche cells,delineating the establishment and disruption of testicular immune homeostasis during human spermatogenesis,investigating abnormal spermatogenesis in humans,and,ultimately,elucidating the molecular evolution of mammalian spermatogenesis.
文摘Objective:To investigate the successive morphological stages of spermatogenesis,hormonal regulation,and testosterone profile in dromedary camel reproduction.Methods:Testicular tissue samples were obtained from 12 dromedary bull camels aged 7 to 8 at a local abattoir.The histological assessment involved tissue processing,hematoxylin and eosin(H&E)staining,and examination under a microscope.Stereological analysis,germ cell identification,and assessment of seminiferous tubules and maturation were conducted.Testosterone assay was performed by radioimmunoassay using blood samples collected at regular intervals.Results:The study revealed 12 phases of the dromedary camel's seminiferous epithelium cycle,highlighting distinct morphological characteristics and cellular processes.Acrosomal migration,maturation,cap formation,and the Golgi-mediated synthesis of proacrosomal vesicles were also explained in dimension,as were the steps of acrosome biogenesis.Spermatids and mature sperm cells were present when spermatogenesis phases were examined.An analysis of the dimensions of seminiferous tubules revealed specific measures for diameter,area,and epithelial height about luminal characteristics.Moreover,there were noticeable variations in the serum testosterone concentrations during the study period,indicating temporal dynamics.Conclusions:This study outlines the spermatogenesis process in dromedary camels across 12 stages,emphasizing cellular dynamics and acrosomal biogenesis.It also provides seminiferous tubule measurements and observes seasonal testosterone fluctuations,offering insights into reproductive regulation and potential strategies for camel breeding conservation.
基金Weifang Fundamental Research Projects,No.WFWSJK-2023-052.
文摘BACKGROUND Pituitary stalk interruption syndrome(PSIS)is a rare anatomical defect of the pituitary gland falling under the spectrum of holoprosencephaly phenotypes.It is characterized by a deficiency in anterior pituitary hormones,such as growth hormone,gonadotropins,and thyroid hormones.Due to the syndrome's rarity and nonspecific manifestations,there is a lack of standardized treatment strategies.Consequently,early diagnosis through imaging and on-time intervention are crucial for improving patients’outcomes.CASE SUMMARY A 30-year-old man presented with absent secondary sexual characteristics and azoospermia.Laboratory evaluation revealed a deficiency in gonadotropins,while thyroid function was mostly within normal ranges.Magnetic resonance imaging of the pituitary gland showed pituitary stalk agenesis,hypoplasia of the anterior pituitary,and ectopic posterior pituitary,leading to the diagnosis of PSIS.Initially,the patient underwent 6 mo of gonadotropin therapy without significant changes in hormone levels and secondary sexual characteristics.Pulsatile gonadotropin-releasing hormone therapy was then administered,resulting in the detection of sperm in the semen analysis within 3 mo.After 6 mo,routine semen tests showed normal semen quality.The couple faced challenges in conceiving due to abstinence and underwent three cycles of artificial insemination,which was unsuccessful.They also attempted in vitro fertilization,but unfortunately,the woman experienced a miscarriage 10 wk after the embryo transfer.CONCLUSION Early detection,accurate diagnosis,and timely treatment are crucial in improving the quality of life and fertility of PSIS patients.
文摘Morphology of the male reproductive system, chromosome behaviors during meiosis and spem tail structures in Homoptera and Heteroptera are compared in this paper. The sheathed testis is found in Fulgoroidea and Heteroptera, and unsheathed testis occurs in Cicadoidea, Cicadelloidea, Cercopoidea, Membracoidea, Psyloidea, Aphidoidea, Aleyrodoidea and Coccoidea. The testis also can be divide into three types by the shape of testicular follicles. The sphere-shaped type is found in Cicadoidea, Cicadelloidea, Cercopoidea, Membracoidea, Aphidoidea and Aleyrodoidea, the tube-shaped type observed in Fulgoroidea, Psyloidea and Coccoidea, and the lamella-shaped type represented by Heteroptera. It is suggested the unsheathed testis may be the primitive type in Homoptera. Meiosis can be divided into 6 type at least, i.e. 1） Cicadoid type; 2） Fulgoroid type; 3） Psyloid type; 4） Aphidoid type; 5） Aleyrodoid type; and 6） Coccoid type. At least four groups exhibit a diffuse stage during meiosis prophase l, they are Psyloidea, Fulgoroidea, Coccoidea and Heteroptera. Sperm tail structures are similar to those reported from other insects with a typical 9＋9＋2 axoneme except that in Aleyrodoidea and Coccoidea whose sperm tail is degenerated.
基金the Science and Technology Projects of Shenzhen(No.JCYJ20160428173152329)the Fundamental Research Funds for the Central Universities(No.21617316)+1 种基金the Guangdong Medical Research Fund(No.A2019553)the National Natural Science Foundation of China(No.81773277).
文摘Phosphoribosyl-pyrophosphate synthetase 2(PRPS2)is a rate-limiting enzyme and plays an important role in purine and pyrimidine nucleotide synthesis.Recent studies report that PRPS2 is involved in male infertility.However,the role of PRPS2 in hypospermatogenesis is unknown.In this study,the relationship of PRPS2 with hypospermatogenesis and spermatogenic cell apoptosis was investigated.The results showed that PRPS2 depletion increased the number of apoptotic spermatogenic cells in vitro.PRPS2 was downregulated in a mouse model of hypospermatogenesis.When PRPS2 expression was knocked down in mouse testes,hypospermatogenesis and accelerated apoptosis of spermatogenic cells were noted.E2F transcription factor 1(E2F1)was confirmed as the target gene of PRPS2 and played a key role in cell apoptosis by regulating the P53/Bcl-xl/Bcl-2/Caspase 6/Caspase 9 apoptosis pathway.Therefore,these data indicate that PRPS2 depletion contributes to the apoptosis of spermatogenic cells and is associated with hypospermatogenesis,which may be helpful for the diagnosis of male infertility.
文摘To investigate the effect of arsenic on spermatogenesis. Methods: Mature (4 months old) Wistar rats were intraperitoneally administered sodium arsenite at doses of 4, 5 or 6 mg-kg^-day1 for 26 days. Different varieties of germ cells at stage VII seminiferous epithelium cycle, namely, type A spermatogonia (ASg), preleptotene spermatocytes (pLSc), midpachytene spermatocytes (mPSc) and step 7 spermatids (7Sd) were quantitatively evaluated, along with radioimmunoassay of plasma follicle-stimulating hormone (FSH), lutuneizing hormone (LH), testosterone and assessment of the epididymal sperm count. Results: In the 5 and 6 mg/kg groups, there were significant dose-dependent decreases in the accessory sex organ weights, epididymal sperm count and plasma concentrations of LH, FSH and testosterone with massive degeneration of all the germ cells at stage VII. The changes were insignificant in the 4 mg/kg group. Conclusion: Arsenite has a suppressive influence on spermatogenesis and gonadotrophin and testosterone release in rats.
文摘Spermatogenesis is a complex process regulated by endocrine and testicular paracrine/autocrine factors. Gonadotropins are involved in the regulation of several testicular paracrine factors, mainly of the IL-1 family and testicular hormones. Testicular cytokines and growth factors (such as IL-1, IL-6, TNF, IFN-γ, LIF and SCF) were shown to affect both the germ cell proliferation and the Leydig and Sertoli cells functions and secretion. Cytokines and growth factors are produced by immune cells and in the interstitial and seminiferous tubular compartments by various testicular cells, including Sertoli, Leydig, peritubular cells, spermatogonia, differentiated spermatogonia and even spermatozoa. Corresponding cytokine and growth factor receptors were demonstrated on some of the testicular cells. These cytokines also control the secretion of the gonadotropins and testosterone in the testis. Under pathological conditions the levels of pro-inflammatory cytokines are increased and negatively affected spermatogenesis. Thus, the expression levels and the mechanisms involved in the regulation of testicular paracrine/autocrine factors should be considered in future therapeutic strategies for male infertility.
文摘Aim:To determine the effect of oral administration of an aqueous extract from the roots of Lepidium meyenii(maca)on spermatogenesis in adult male rats.Methods;Male rats received an aqueous extract of the root(66.7 mg in onemL)twice a day for 14 consecutive days.Results:Treatment with Lepidium meyenii resulted in an increase in theweights of testis and epididymis but not the seminal vesicle weight.The length and frequency of stages IX-XIV seminif-erous tubules,where mitosis occurred,were increased and stages I-VI were reduced in rats treated with Lepidiummeyenii.Conclusion;The Lepidium meyenii root invigorates spermatogenesis in male rats by acting on its initialstages(IX-XIV).
基金Acknowledgment This work was supported by grants from National Natural Science Foundation of China （No. 30471729） and the ＂211＂ Project of the ＂Tenth-Five＂ Program for Peking University Health Science Center, China （No. 219）.
文摘Aim： To investigate the expression and subcellular localization of chemokine-like factor superfamily 2 （CKLFSF2） in human testis and its potential role in spermatogenesis. Methods： A specific polyclonal antibody against CKLFSF2 was raised. The expression and cellular localization of CKLFSF2 in the seminiferous tubules was checked by immunohistochemistry method. Also, in situ hybridization was applied to localize the mRNA distribution. The EGFP- CKLFSF2 fusion protein was expressed in COS-7 cells to localize its subcellular location in vitro. In addition, the abnormal expression of CKLFSF2 in testes of patients with male infertility was assayed by reverse transcription polymerase chain reaction （RT-PCR） and immunohistochemistry methods. Results： Having a close correlation with spermatogenesis defects, CKLFSF2 was specifically expressed in meiotic and post-meiotic germ cells, which were localized to the endoplasmic reticulum （ER） near the Golgi apparatus. Conclusion： CKLFSF2 could play important roles in the process of meiosis and spermiogenesis, and might be involved in the vesicular transport or membrane apposition events in the endoplasmic reticulum.
文摘The effects of diabetes mellitus include long-term damages, dysfunctions, and failures of various organs. An important complication of diabetes is the disturbance in the male reproductive system. Glucose metabolism is an important event in spermatogenesis. Moreover, glucose metabolism is also important for maintaining basic cell activity, as well as specific functions, such as motility and fertilization ability in mature sperm. Diabetic disease and experimentally induced diabetes both demonstrated that either type 1 diabetes or type 2 diabetes could have detrimental effects on male fertility, especially on sperm quality, such as sperm motility, sperm DNA integrity, and ingredients of seminal plasma. Epigenetic modifications are essential during spermatogenesis. The epigenetic regulation represents chromatin modifications including DNA methylation, histone modifications, remodeling of nucleosomes and the higher-order chromatin reorganization and noncoding RNAs. If spermatogenesis is affected during the critical developmental window, embryonic gonadal development, and germline differentiation, environmentally-induced epigenetic modifications may become permanent in the germ line epigenome and have a potential impact on subsequent generations through epigenetic transgenerational inheritance. Diabetes may influence the epigenetic modification during sperm spermatogenesis and that these epigenetic dysregulation may be inherited through the male germ line and passed onto more than one generation, which in turn may increase the risk of diabetes in offspring.
基金This work was supported by the National Basic Research Program （Nos. 2013CB947900, 2013CB945502 and 2014CB943101） of China （973）, by grants from National Natural Science Foundation of China （No. 31371519） and the Knowledge Innovation Program of the Chinese Academy of Sciences （No. KSCX2-EW-R-07）.
文摘The blood-testis barrier （BTB） is found between adjacent Sertoli cells in the testis where it creates a unique microenvironment for the development and maturation of meiotic and postmeiotic germ cells in seminiferous tubes. It is a compound proteinous structure, composed of several types of cell junctions including tight junctions （TJs）, adhesion junctions and gap junctions （GJs）. Some of the junctional proteins function as structural proteins of BTB and some have regulatory roles. The deletion or functional silencing of genes encoding these proteins may disrupt the BTB, which may cause immunological or other damages to meiotic and postmeiotic cells and ultimately lead to spermatogenic arrest and infertility. In this review, we will summarize the findings on the BTB structure and function from genetically-modified mouse models and discuss the future perspectives.
文摘We investigated whether letrozole （2.5 mg day-1） improves sperm count in non-obstructive azoospermia （NOA） patients. Four men were included in this study, and they had folliculo-stimulating hormone and other hormone levels within the normal range and no varicoceles or chromosomal aberrations. These four patients were administered letrozole for 3 months. Sperm count, testicular volume, gonadotropin, testosterone （T） and estradiol （E2） blood levels were assessed before, during and 1 week after the suspension of treatment. All patients showed spermatozoa in their ejaculate, increased gonadotropin and T levels and lower E2 levels （P〈0.05 in all cases）, when letrozole was administered. This suggests that letrozole treatment might improve sperm count in an NOA sub-population; however, more studies, including the proper controls, are needed to confirm its efficacy.
文摘Aim： To determine whether vasectomy away from the epididymal tail （via the inguinal canal） in rabbits can reduce the early postoperative effects on spermatogenesis. Methods： Twenty-nine normal male Japanese white rabbits （aged 4- 6 months） were subjected to unilateral close-ended （conventional） or open-ended （the cut end of the juxta-epididymal vas deferens not ligated） vasectomy via the inguinal canal. Ten days and 3 months after operation, testes, epididymides and vasa deferentia were removed and methacrylate resin-embedded sections prepared. The histology of the testis, epididymis and vas deferens was examined under light microscope, and the volume and diameter of the seminiferous tubules were quantitatively studied using stereological methods. Results： Neither of the methods of vasectomy led to apparent damage to spermatogenesis on the vasectomized side in comparison with the contralateral shamoperated side, but the juxta-epididymal vas deferens on the vasectomized side was highly distended and contained numerous sperm 3 months after operation. Conclusion： Vasectomy away from the cauda epididymis has no significant early postoperative effects on spermatogenesis in rabbits.
文摘Both pulsatile gonadotropin-releasing hormone （GnRH） infusion and combined gonadotropin therapy （human chorionic gonadotropin and human menopausal gonadotropin [HCG/HMG]） are effective to induce spermatogenesis in male patients with congenital hypogonadotropic hypogonadism （CH H）. However, evidence is lacking as to which treatment strategy is better. This retrospective cohort study included 202 patients with CHH： twenty had received pulsatile GnRH and 182 had received HCG/HMG. Patients had received therapy for at least 12 months. The total follow-up time was 15.6 ± 5.0 months （range： 12-27 months） for the GnRH group and 28.7 ± 13.0 months （range： 12-66 months） for the HCG/HMG group. The median time to first sperm appearance was 6 months （95% confidence interval [CI]： 1.6-10.4） in the GnRH group versus 18 months （95% Ch 16.4-20.0） in the HCG/HMG group （P〈 0.001）. The median time to achieve sperm concentrations 〉5 x 106 m1-1 was 14 months （95% Ch 5.8-22.2） in the GnRH group versus 27 months （95% Ch 18.9-35.1） in the HCG/HMG group （P 〈 0.001）, and the median time to concentrations 〉10 x 106 m1-1 was 18 months （95% Ch 10.0-26.0） in the GnRH group versus 39 months （95% CI unknown） in the HCG/HMG group. Compared to the GnRH group, the HCG/HMG group required longer treatment periods to achieve testicular sizes of 〉4 ml, 〉8 ml, 〉12 ml, and 〉16 ml. Sperm motility （a ＋ b ＋ c percentage） evaluated in semen samples with concentrations 〉1 × 106 ml-1 was 43.7% ± 20.4% （16 samples） in the GnRH group versus 43.2% ± 18.1% （153 samples） in the HCG/HMG group （P= 0.921）. Notably, during follow-up, the GnRH group had lower serum testosterone levels than the HCG/HMG group （8.3 ±4.6 vs 16.2 ± 8.2 nmol 1-1, P 〈 0.001）. Our study found that pulsatile GnRH therapy was associated with earlier spermatogenesis and larger testicular size compared to combined gonadotropin therapy. Additional prospective randomized studies would be required to confirm these findings.
基金This work was supported by the National Natural Science Foundation of China （Number 31371174）, the Natural Science Foundation of Jiangsu Province, China （Number BK20131230）, and the Postgraduate Research and Practice Innovation Program of Jiangsu Province, China （KYCX17-1893）. We thank Dr. Wilkinson （University of California, USA） for kindly providing Rhox 10 antibody.
文摘To clarify the functions and mechanism of stimulated by retinoic acid gene 8 （Stra8） in spermatogenesis, we analyzed the testes from Stra8 knockout and wild-type mice during the first wave of spermatogenesis. Comparisons showed no significant differences in morphology and number of germ cells at 11 days postpartum, while 21 differentially expressed genes （DEGs） associated with spermatogenesis were identified. We speculate that Stra8 performs many functions in different phases of spermatogenesis, such as establishment of spermatogonial stem cells, spermatogonial proliferation and self-renewal, spermatogonial differentiation and meiosis, through direct or indirect regulation of these DEGs. We therefore established a preliminary regulatory network of Stra8 during spermatogenesis. These results will provide a theoretical basis for further research on the mechanism underlying the role of Stra8 in spermatogenesis.
基金funded,in part,by the National Basic Research Program of China(973 programNo.2013CB943103)+1 种基金the National Natural Science Foundation of China(No.31272439,No.31230048 and No.31572401)Programs Foundation of Ministry of Education of China(No.20130204110017)
文摘Mammalian spermatogenesis contains three continuous and organized processes, by which spermatogonia undergo mitosis and differentiate to spermatocytes, follow on meiosis to form haploid spermatids and ultimately transform into spermatozoa. These processes require an accurately, spatially and temporally regulated gene expression patterns. The microRNAs are a novel class of post-transcriptional regulators. Cumulating evidences have demonstrated that microRNAs are expressed in a cell-specific or stage-specific manner during spermatogenesis. In this review, we focus on the roles of microRNAs in spermatogenesis. We highlight that N6-methyladenosine(m6A)is involved in the biogenesis of microRNAs and miRNA regulates the m6A modification on mRNA, and that specific mi RNAs have been exploited as potential biomarkers for the male factor infertility, which will provide insightful understanding of microRNA roles in spermatogenesis.
